.CIDB File Extension

Contains information about CDs that have been loaded using iTunes; includes album and track names downloaded from the CDDB (Compact Disc Database) as well as CD and track name for CDs that are burned by the user; named "CD Info.cidb" by default.

The "CD Info.cidb" file is located in Mac OS X in the
"/Users/username/Library/Preferences" folder.

In Windows XP, it is located in the "\Documents and Settings\username\Application Data\Apple Computer\iTunes" directory.

In Windows Vista, it is stored in the "/Users/username/AppData/Roaming/Apple Computer/iTunes" folder.